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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment to Accounting Pronouncements (Details) - USD ($)	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Property and Equipment
Impairment of property and equipment	$ 0	$ 200,000
Impairment charges		$ 485,270
Revenue Recognition
Practical expedient, financing components	true
Insurance
Letter of credit issued for worker's compensation insurance carrier as part of the entity's self-insured loss control program	$ 500,000
Contract Costs
Practical expedient to expense as incurred any incremental costs to obtain and fulfill customer contracts	true
Buildings and improvements \| Minimum
Property and Equipment
Estimated useful lives	5 years
Buildings and improvements \| Maximum
Property and Equipment
Estimated useful lives	40 years
Warehouse equipment \| Minimum
Property and Equipment
Estimated useful lives	3 years
Warehouse equipment \| Maximum
Property and Equipment
Estimated useful lives	15 years
Furniture, fixtures and leasehold improvements \| Minimum
Property and Equipment
Estimated useful lives	1 year
Furniture, fixtures and leasehold improvements \| Maximum
Property and Equipment
Estimated useful lives	12 years
Vehicles \| Minimum
Property and Equipment
Estimated useful lives	2 years
Vehicles \| Maximum
Property and Equipment
Estimated useful lives	5 years